libexif: update to 0.6.21

Signed-off-by: W. Michael Petullo <mike@flyn.org>

libs/libexif/Makefile

@@ -8,12 +8,12 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=libexif
-PKG_VERSION:=0.6.19
+PKG_VERSION:=0.6.21
 PKG_RELEASE:=1
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.bz2
 PKG_SOURCE_URL:=@SF/libexif
-PKG_MD5SUM:=56144a030a4c875c600b1ccf713f69f7
+PKG_MD5SUM:=27339b89850f28c8f1c237f233e05b27
 
 PKG_FIXUP:=autoreconf
 PKG_INSTALL:=1